Products including Infants' and Children's Tylenol and Infants' and Children's Motrin were found to contain tiny metal particles. Prosecutors claimed that McNeil was aware of the problem for nearly a year, after receiving a consumer complaint, but failed to take corrective action.

According to the criminal charge, the medicines were adulterated because they were not manufactured, processed, packed or held in conformance with current Good Manufacturing Practices (cGMP), in violation of the federal Food, Drug and Cosmetic Act.

In Federal District Court in Philadelphia on Tuesday, McNeil agreed to pay a criminal fine of $20 million and forfeit $5 million.

The company also remains subject to a permanent injunction entered by the U.S. District Court in 2011. This requires the company, among other things, to take remedial measures before reopening its manufacturing facility in Fort Washington, Pa.

"The law requires that drugs be produced under the most rigorous of quality standards," commented First Assistant U.S. Attorney Lappen. "When companies fail to exercise the vigilance that the law demands, they will held be accountable. Drug companies should be aware that failing to adhere to good manufacturing practices subjects them to penalties and prosecution."